# std::rename

From cppreference.com
< cpp‎ | io‎ | c

Defined in header `<cstdio>` |  |
int rename( const char* old_filename, const char* new_filename ); |  |

Changes the filename of a file. The file is identified by character string pointed to by old_filename. The new filename is identified by character string pointed to by new_filename.

If new_filename exists, the behavior is implementation-defined.

### Parameters

old_filename | - | pointer to a null-terminated string containing the path identifying the file to rename
new_filename | - | pointer to a null-terminated string containing the new path of the file

### Return value

​0​ upon success or non-zero value on error.

### Notes

POSIX specifies many additional details on the semantics of this function, which are reproduced in C++ by std::filesystem::rename.

### Example

Run this code

    #include <cstdio>
    #include <cstdlib>
    #include <fstream>
    #include <iostream>

    int main()
    {
        if (!std::ofstream("from.txt").put('a')) // create and write to file
        {
            std::perror("Error creating from.txt");
            return EXIT_FAILURE;
        }

        if (std::rename("from.txt", "to.txt"))
        {
            std::perror("Error renaming");
            return EXIT_FAILURE;
        }

        std::cout << std::ifstream("to.txt").rdbuf() << '\n'; // print file
        return EXIT_SUCCESS;
    }

Output:

    a

### See also

rename (C++17) | moves or renames a file or directory (function)
remove | erases a file (function)
C documentation for rename

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